This invention relates to the problem that public utilities have an unattended electric power substations in gaining telephone access to multiple telephone handsets and/or auto-dial/auto-answer modem-equipped devices. In the past separate telephone lines were used for each telephone handset and/or auto-dial/auto-answer modem-equipped device. Our invention, an exchange, connects one public-switched telephone line and multiple output ports for interconnection to the telephone handsets and/or auto-dial/auto-answer modem-equipped devices. This invention allows the calling station to select which handset or device is to be connected and rung by entering a dual-tone multi-frequency code. In the absence of a device selection code the default port number one will be connected and rung which typically would be the telephone handset. This invention makes possible a planned priority of use of the public telephone line by the connected devices.